by jchesshyre Fri 13 Jun 2014, 1:06 pm
Did it work? Well yes and no. When I wrote that message I had 112000 on the clock; I've since reached 150000 and that bike is now in retirement as a donor vehicle because it was using too much oil. (Found one on ebay with 13000 on the clock : ) )
I would describe the 'fix' I listed as more palliative care than a cure. It delays the problem but doesn't cure it, unfortunately. I never bought another tensioner after I did it, but the noise did get gradually worse, just more gradually than it had been before without the fix. Each time it started again I'd adjust the bolt (sometimes screwing it in, sometimes out worked, always being careful not to make it so tight that it affected the tensioner's action), but there came a time when the noise was either there when cold or when warmed up – if I set the bolt so that it was silent when cold it rattled once warmed up, and vice versa. I just got used to it.
So I still don't know what a real cure for the problem is. It is worth pointing out that in my investigations I realised that the sound, contrary to what many people conclude, is not the cam chain rattling, it is the plunger in the tensioner rattling. I guess that as the cam chain wears (mine *looked* pristine when I did the valves as mentioned above but after 112000 it had to have some wear) the tensioner has a more difficult job, or something. It's just frustrating that these engines seem to be able to go on and on, but that the tensioner doesn't seem to have been designed with this in mind.
So I would say try the fix (but as I say being VERY careful not to tighten the bolt so much that it starts winding the tensioner) but ultimately the noise will probably come back, but maybe 20000 miles later instead of 5000.
My new CB is still silent in this regard...I seem to remember my previous one started doing it around 60000, oddly enough literally just after I'd changed from using Castrol GPS to Silkolene Comp4 (explanation?), and at that point it was only around 2-3k rpm. Later on it did it loudly at idle until fully warmed up. It never seemed to affect performance – my CB ran more or less as well at 150000 miles as it had at 24000. And the cam chain always looked new as I said. The only point I noticed was that each time I gave up on a tensioner and changed it for a new one (roughly every 20-30000 miles) there was a shiny, polished area on the end of the plunger that contacts the blade.
Good luck!